包穗突变体sui1-5鉴定及OsPSS1互作蛋白筛选  

Identification of sheathed panicle mutant sui1-5 and screening of OsPSS1 interaction protein in rice(Oryza sativa L.)

作　　者：杨晔 孙琦[2] 邢欣欣 张海涛[1] 赵志超[2] 程治军[2] YANG Ye;SUN Qi;XING Xin-Xin;ZHANG Hai-Tao;ZHAO Zhi-Chao;CHENG Zhi-Jun(College of Agronomy,Anhui Agricultural University,Hefei 230036,Anhui,China;Institute of Crop Sciences,Chinese Academy of Agricultural Sciences,Beijing 100081,China)

机构地区：[1]安徽农业大学农学院,安徽合肥230036 [2]中国农业科学院作物科学研究所,北京100081

出　　处：《作物学报》2023年第3期597-607,共11页Acta Agronomica Sinica

基　　金：国家自然科学基金项目(31871603)资助。

摘　　要：包穗是水稻生产上的不利性状,表现为倒一节间伸长异常,穗部不能正常从叶鞘伸出。目前,已经鉴定报道了多个包穗性状突变体,但对该性状产生的分子机制认识仍然有限。OsPSS1/SUI1是一个磷脂酰丝氨酸合酶的编码基因,该基因突变会引起突变体sui1-4的倒一节间严重缩短。我们鉴定到了一个新的OsPSS1/SUI1等位突变体sui1-5,该突变体倒一节间缩短程度明显减轻。测序发现突变体中基因SUI1的第7个外显子存在1个单碱基G→T替换,导致甘氨酸突变为缬氨酸。为了研究OsPSS1的功能,我们通过酵母筛库发现了一个与OsPSS1互作的蛋白GH9A3,并通过酵母双杂交、荧光素酶互补(LCI)和双分子荧光互补(BIFC)实验加以验证。GH9A3是GH9基因家族成员,编码内切-1,4-β葡聚糖酶,推测是细胞壁成分纤维素合成的一个关键酶。在苗期,SUI1和互作蛋白编码基因GH9A3的表达量并不同步,GH9A3在sui1-5的表达量上调。但是在拔节抽穗期,SUI1和GH9A3在sui1-5中的表达量都相应降低,其他纤维素合酶CESAs家族基因的表达量在sui1-5中也明显降低。这些结果为进一步研究OsPSS1的功能奠定了一定的理论基础。The sheathed panicle phenomenon is a disadvantageous trait in agricultural production,which is mainly due to the abnormal elongation of the uppermost internode,resulting in the panicle closed by flag leaf sheath.Although some mutants of sheathed panicle have been identified and reported in rice,the underling molecular mechanism of uppermost internode shortening is still poorly understood.OsPSS1/SUI1 is a phosphatidylserine synthase gene and the mutation of Os PSS1 leads to a severe shortening of the uppermost internode of mutant sui1-4.We discovered and identified a new allelic mutant sui1-5 of SUI1 and the degree of the uppermost internode shortening in sui1-5 was significantly reduced.Sequence analysis revealed a single nucleotide substitution of G to T at the seventh exon of SUI1 in sui1-5,resulting in an amino acid change from glycine to valine.To study the function of Os PSS1,we detected a protein GH9A3 interacting with SUI1 through a yeast screening library,which was verified by yeast two-hybrid,luciferase complementarity(LCI),and bimolecular fluorescence complementarity(BiFC).GH9A3 was a member of GH9 gene family,encoding an endo-β-1,4-glucanase which was speculated to be a key enzyme in cell wall cellulose synthesis.At seedling stage,the relative expression level of SUI1 was not synchronized with that of interaction protein-coding gene GH9A3,and the relative expression level of GH9A3 was up-regulated in sui1-5.But at heading and jointing stage,the relative expression level of SUI1 and GH9A3 decreased synchronously,and the relative expression level of other cellulose synthase CESAs family genes decreased obviously in sui1-5.These results lay a foundation for further study of the function of Os PSS1.

关 键 词：包穗 SUI1 GH9A3 精细定位 纤维素合酶 

分 类 号：S511[农业科学—作物学]